1. Field of the Invention
The present invention generally relates to electrical terminal fastening dies and a electrical terminal fastening method to be applied to e.g. an electric vehicle, wherein an exposed conductor of an electric wire is inserted into an electrical terminal and the conductor is fastened to the terminal.
2. Description of the Related Art
A fastening method of an electrical terminal 80 as in FIGS. 9A-9C has been proposed.
According to the method, as shown in FIG. 9A, a conductor 81 of an electric wire (not shown) is exposed, the conductor 81 is inserted into the electrical terminal 80 having a circular section, and the electrical terminal 80 is arranged between a couple of dies 82 each having a pressing groove 83 with a section formed by symmetrically dividing a hexagon. And, as shown in FIG. 9B, the electrical terminal 80 is fastened to the conductor 81 by closing the pair of dies 82. The fastened terminal 80 has a hexagonal section.
However, since a material is apt to flash between abutting planes 82a of the couple of dies 82 when the electrical terminal 80 is fastened, a flash 84 would arise on both sides of an fastened electrical terminal 80xe2x80x2 as shown in FIG. 9C. This needs work of cutting the flash 84 in order to satisfy a standard.
Therefore, another fastening method shown in FIG. 10 disclosed in Japanese Patent Application Laid-open No. 10-22040 (hereinafter, JP""040 ) has been proposed in order to prevent the flash 84. According to this fastening method, as shown in FIG. 10A, a couple of dies 82 form flash absorbing grooves 85 on an entrance side of a pressing groove 83, and as shown in FIG. 10B, a flash formed on the electrical terminal 80 is absorbed in the flash absorbing groove 85.
With respect to the above prior art fastening method of JP""040, however, as shown in FIG. 10C, since a pair of oppositely located round flashes 86 are formed on the fastened electrical terminal 80xe2x80x3 and in the respective flash absorbing grooves 85, a diagonal distance L including the pair of round flashes 86 is of nonstandardized one. Therefore, the fastened electrical terminal 80xe2x80x3 satisfying a standard can not be obtained with the fastening work.
In view of the foregoing, an object of the present invention is to provide electrical terminal fastening dies and an electrical terminal fastening method for forming an electrical terminal capable of easily satisfying a standard, wherein cutting work of a flash is not required after fastening work.
In order to achieve the above-described object, as a first aspect of the present invention, electrical terminal fastening dies includes: an electric wire; an electrical terminal having the electric wire therein; a couple of dies to press the electrical terminal a substantially hexagon in cross section; an abutting plane provided on each of the couple of dies; a pressing groove provided on the abutting plane and having a section to be formed by dividing a hexagon symmetrically with a diagonal; a pair of terminal pressing planes formed on a surface of the pressing groove of at least either one of the couple of dies for pressing the electrical terminal; and a pair of flash preventing planes formed on the surface of the pressing groove having the pair of terminal pressing planes, and each connected to the abutting plane, for pressing the electrical terminal to form thin portions thereon so as to prevent a flash from arising on the electrical terminal.
According to the above-described structure, since the pair of flash preventing planes are provided on the pressing groove, the thin portion can be formed on the electrical terminal instead of a flash conventionally formed.
As a second aspect of the present invention, in the structure with the above first aspect, the pair of flash preventing planes each have an inclination nearer the horizontal than that of the pair of terminal pressing planes for surely forming the thin portion and width between the connecting points of the abutting plane and the pair of flash preventing planes is defined equally to a specified dimension of a corresponding part of the electrical terminal as a finished product.
According to the above-described structure, since cutting work of a flash can be eliminated, the fastening work of an electrical terminal can be executed quickly.
As a third aspect of the present invention, in the structure with the above first or second aspect, a pressing projection is oppositely provided on each of the pressing grooves for forming a pair of opposite recesses on the electrical terminal so as to strongly pressing the electrical terminal to the electric wire.
According to the above-described structure, since the electrical terminal is strongly fastened to the electric wire by means of the pressing projections, movement of the electric wire in the electrical terminal can be prevented.
As a fourth aspect of the present invention, an electrical terminal fastening method includes the steps of: inserting an electric wire into an electrical terminal; putting the electrical terminal between pressing grooves formed on a couple of dies, respectively, the pressing grooves each having a section to be formed by dividing a hexagon symmetrically with a diagonal and at least one of the pressing grooves having a pair of flash preventing planes at an entrance thereof; and pressing the electrical terminal a substantially hexagon in cross section by the couple of dies so as to fastening the electrical terminal to the electric wire, wherein thin portions are formed on the electrical terminal so as to prevent a flash from arising on the electrical terminal.
According to the above-described structure, since the pair of flash preventing planes are provided on the pressing groove, the thin portion can be formed on the electrical terminal instead of a flash conventionally formed. Since cutting work of a flash can be eliminated, the fastening work of an electrical terminal can be executed quickly.
As a fifth aspect of the present invention, in the structure with the above fourth aspect, the electrical terminal is pressed by a pressing projection oppositely provided on each of the pressing grooves so as to strongly fasten the electrical terminal to the electric wire by forming a pair of opposite recesses on the electrical terminal.
According to the above-described structure, since the electrical terminal is strongly fastened to the electric wire, movement of the electric wire in the electrical terminal can be prevented.
As a sixth aspect of the present invention, in the structure with the above fifth aspect, the electrical terminal is pressed every 60 degrees three times by the couple of dies for forming three pairs of recesses on the electrical terminal so as to more strongly fastening the electrical terminal to the electric wire.
According to the above-described structure, since six recesses are formed on the electrical terminal, the electrical terminal can be more strongly fastened to the electric wire. And, the thin portion becomes shorter, the electrical terminal can be easily handled.
The above and other objects and features of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings.